1. Field of the Invention
The present invention relates to an analog electronic timepiece capable of displaying times in various areas of the world.
2. Description of the Related Art
In the related art, an electronic timepiece capable of displaying local times in various areas of the world has been known. According to the electronic timepiece, when any one time zone is designated by a user input operation and the like, local time in the time zone is calculated and displayed based on time difference information from coordinate universal time (UTC), and the like. Also, an electronic timepiece having a world time clock function of simultaneously or switchingly displaying local time in a desired area of the world in addition to the display of the usual time (local time) has been known.
According to an analog electronic timepiece configured to display date and time with hands, a peripheral edge portion of a dial plate at which marks and scales are arranged, a bezel or the like is provided with local time marks such as cities of the world indicating respective time zones, areas and time differences from coordinate universal time (UTC) in an annular shape. A user is enabled to designate a desired time zone by indicating any one of the local time marks with one hand, and local time is calculated and displayed in the designated time zone.
In the meantime, an electronic timepiece (a radiowave timepiece) has been recently known which is configured to receive radiowaves (a navigation message) from positioning satellites, to perform positioning, to determine a time zone to which the obtained position belongs, and to calculate and display local time in the time zone. The radiowaves from the positioning satellites can be received in various areas of the world in which the radiowaves can be received such as open outdoors. Thus, an appropriately setting can be made even though a user does not recognize a time zone at a current position.
However, in some areas of the world, for the summer season, the daylight saving time (Daylight Saving Time (DST)) during which time is made to deviate from the standard time of local time in a time zone is implemented. Therefore, in order to correctly display the local time, it is necessary to count and display date and time by additionally deviating a shift time during the daylight saving time implementation from the standard time over a daylight saving time implementation time period. Regarding this, JP-A-2011-048777 discloses a technology of associating and storing information about daylight saving time implementation time periods with respective areas of the world, determining start date and time and end date and time of the daylight saving time by using date and time information acquired from GPS satellites and correcting date and time during the daylight saving time implementation.
However, whether the daylight saving time is to be implemented and an implementation time period of the daylight saving time are determined within a range narrower than a setting range of the time zones, in many cases, and a plurality of areas in which different daylight saving time implementation rules are determined even in the same time zone is sometimes mixed. Therefore, in the analog electronic timepiece, when a local time setting by designation of a preset time zone and a local time setting based on any positional information such as positioning data are used in combination, even though a time zone is designated, it may not possible to automatically select an appropriate daylight saving time implementation rule and to apply the daylight saving time. As a result, the user may not recognize whether the daylight saving time corresponding to the current position has been applied to the calculated local time.